1: Stop running at Peach with nair. If you hit, you'll get like 40 damage from a CC dsmash. Against CC spammers you have to answer back with a game based almost entirely around grab and drill. Dair can't be CCed and obviously neither can grabs. Both moves lead to your efficient finishers on Peach: Usmash and Uair.
2: The three things you should be spamming to hell, you need to work on: drillshine->grab (->uair), drillshine->usmash for kills, and just flat out DD mindgames then grab both damage AND kills.
3: Use your shield more. You got hit by alot of random nairs and fairs. If you miss a drill, grab or nair - don't sidestep. Dsmash will rip through your Fox after the side-step is done anyways, so just roll backwards and retry your approach.
4: Learn to d.i. better. Everytime Peach naired you in the first match, you went on this awkward down-ish angle. You need to survival d.i. them so you don't die that easily from indirect nairs.
In conclusion:
Roll if you miss, shine if you don't. More grabs and ALOT more drill. Don't forget to just block her aerials and roll or jump out of shield sometimes. You don't have to always run into her moves. Try playing it safer.
Remember though, safer doesn't necessarily mean slower. hehe.